This invention relates in general to the field of cattle stalls, and in particular, to milking parlors and milking stalls designed for compactness, efficient parlor operation and maximum comfort for the cow.
A milking parlor generally consists of an array of individual stalls, each designed to hold a cow or other dairy animal while she is being milked. An attendant or operator is usually required to be present at the parlor to perform such tasks as ensuring that the animals are properly situated in the stalls; washing the udders prior to milking; applying milker units; and monitoring and attending to the operation of the milker units.
A recent development in parlor design has yielded the so-called side-by-side or parallel stall configuration. Here, the cow is positioned facing outwardly from the operator and milking takes place at the rear of the cow, between the hind legs. Variations of this design are a v-shaped parlor arrangement and a curved parlor arrangement, the latter being discussed in U.S. Pat. No. 5,000,119 having the same assignee as this matter.
These side-by-side parlors are designed so that cows enter through an entry gate into an aisle or pathway along the rear side of the parlor and then turn approximately ninety degrees and enter the furthest stall that is not yet occupied by a cow.
In order to ensure that the cows proceed as far as they can go before entering a stall, and to ensure that there are no stalls left unoccupied, a scheme of sequencing gates is used for directing the cows down the aisle and into the farthest unoccupied stall.
The milking parlor has a rear wall that defines one side of the entry aisle, dividers which serve as side walls, and an exit gate at the front of each stall. The rear wall defines the milker position, and the cows' hind legs are positioned against this wall. The front or exit gate can be of a swinging or race-gate design with doors that swing open to release the cow, or can be of an upward swinging or lifting design, which moves upward or above the cow to release her from the stall. The sequencing gate forms a part of the side wall that separates the cows from one another. The sequencing gate is preferably a cow-operated swing gate turning on a vertical pivot. In a first position, the gates are disposed across the stalls, and with the rear wall define the entry aisle for the cows into the parlor.
In this position the gate extends across the stall so that a cow will proceed to the next unoccupied stall in sequence. As the cow enters the stall, she swings the gate to a second or open position, which opens the next adjacent stall and blocks off the aisle or passageway. The next cow in sequence is thus directed into the next adjacent stall. The gates are designed with a distal nose position that extends to one side of the pivot. When the cow enters the stall she encounters this nose portion and pushes against it. A major, proximal position extends on the other side of the pivot and in the first position mentioned above extends across the next adjacent stall to deny entry into that stall. When a cow enters the stall and passes against the nose position, she swings the gate major portion out to open the next stall and to block the entry aisle.
The vertical pivot is usually a solid post that extends the height of the sequencing gate. Thus, a solid, non-movable member encounters the widest part of the cow, namely her barrel. Consequently, the stalls must be wider than is actually needed for good positioning and milking, in order to permit the cows to enter and exit comfortably past the non-movable member.
One example of a sequencing gate is shown in U.S. Pat. No. 5,000,119 mentioned earlier. Another sequencing gate is described in U.S. Pat. No. 4,930,447 granted Jun. 5, 1990.